Kakuru is known from an opalised almost complete tibia
(shin bone). It was dug up somewhere in the opal fields of
Andamooka in South Australia, and was first noticed in
a shop window by palaeontologist Neville Pledge of the South
Australian Museum in 1973. The fossil was sold, and remained in private hands
for 30 years, until being bought by the South Australian Museum for $22,000 in 2004.
The generic (first) name is from an Aboriginal legend and means "rainbow
serpent", probably because being opalised the minerals sparkle
with many colours in some places. The species (second) name is a variant
spelling of the Guyani tribe which inhabited the area around Andamooka.

It was a small, perhaps carnivorous theropod about 1.5 to 2 metres (5 to 6
feet) in length. The above reconstruction comes out at 1.7 metres,
with a short Avimimus-like tail. The structure of the tibia suggests that
it belongs to a
completely new family of theropod dinosaurs, unknown of anywhere else in the
world. The tibia, when reconstructed, was found to be in two main sections
which were separated by only a small gap of missing material. It measures
323 mm (about 13 inches)
in total length. In form it resembles Calamospondylus foxii and
Coelurus gracilis, especially in the distal (lower) end.
In general proportions the tibia is similar to Microvenator celer
and Ornitholestes hermanni.

Re-evaluation of the material may suggest a similarity between the tibia
of Kakuru and that of the oviraptorosaur Ingenia yanshi,
especially in the overall shape of the astragular groove,
perhaps indicating that Kakuru may belong somewhere in the
oviraptorosauria. An undescribed tibia and astragalus from Africa are
also said to closely resemble the Kakuru material.

So, how did I manage to reconstruct a dinosaur from a single incomplete
bone? The distal (lower) end of the tibia is diagnostic for most theropods.
Kakuru's tibia, although unique, closely resembles that of the
bird-like Avimimus portentosus from the Late Cretaceous of Mongolia
in some aspects. It is also similar to that of coelurosaurs and modern
slender-legged wading birds. Since it seems to resemble Avimimus
and Ingenia, with proportions similar to Microvenator,
I took skeletal reconstructions of Avimimus and Microvenator
(an oviraptorosaur of about the same age as Kakuru) and used morphing
software to generate a theoretical skeletal reconstruction midway between the two.

The result is an interesting reconstruction of a small long-legged
theropod, although of course being based on a single bone its accuracy is
hard to determine.

The type specimen of Kakuru. Used with permission from the
former owner

Long, J. & B.Choo 1998 Yet more on Australian dinosaurs.Dinonews 12:4-5. Western Australian Museum

Molnar, R.E. & N.S.Pledge 1980 A new theropod dinosaur from South Australia.Alcheringa 4:281-287.